194-69-4Relevant academic research and scientific papers
Methylarene-based PAH synthesis via domino cyclization of 1, 1-difluoro-1-alkenes
Fuchibe, Kohei,Takao, Go,Takahashi, Hiroki,Ijima, Shiori,Ichikawa, Junji
, p. 2019 - 2029 (2019/12/23)
Polycyclic aromatic hydrocarbons (PAHs) containing 4-7 benzene rings were synthesized via a methylarene-based protocol. Trimethyl[2-(trifluoromethyl)allyl]silane was electrophilically benzylated with Ar1CH2Br (prepared from Ar1CH3) to afford 2-trifluoromethyl-1-alkenes that were in turn nucleophilically benzylated with Ar2CH2Li (prepared from Ar2CH3) through an SN2-type reaction to produce 1, 1-difluoroethylenes, which are cyclization precursors bearing two 2-arylethyl groups. Magic acid efficiently promoted the domino FriedelCrafts-type cyclization of these precursors, followed by dehydrogenation that enabled the connection among two aryl groups (Ar1 and Ar2) by forming two benzene rings between them, facilitating the synthesis of the desired higher-order PAHs. With the proposed protocol, the combination of even a limited number of methylarenes can yield a variety of PAHs in diverse configurations.
Polycyclic Aromatic Hydrocarbons via Iron(III)-Catalyzed Carbonyl-Olefin Metathesis
McAtee, Christopher C.,Riehl, Paul S.,Schindler, Corinna S.
supporting information, p. 2960 - 2963 (2017/03/11)
Polycyclic aromatic hydrocarbons are important structural motifs in organic chemistry, pharmaceutical chemistry, and materials science. The development of a new synthetic strategy toward these compounds is described based on the design principle of iron(III)-catalyzed carbonyl-olefin metathesis reactions. This approach is characterized by its operational simplicity, high functional group compatibility, and regioselectivity while relying on FeCl3 as an environmentally benign, earth-abundant metal catalyst. Experimental evidence for oxetanes as reactive intermediates in the catalytic carbonyl-olefin ring-closing metathesis has been obtained.
A convenient and general synthesis of cata- and peri-condensed polycyclic aromatic hydrocarbons with a Fjord-region
Kumar, Subodh
, p. 841 - 844 (2007/10/03)
Cata- and peri-condensed polycyclic aromatic hydrocarbons (PAHs) 10a-d and 11 have been conveniently synthesized by the application of Suzuki cross-coupling reaction. In three to four steps, these PAHs having fjord-region were obtained in an overall yield of 35-51% from commercially or easily accessible aryl boronic acids and aryl bromides.
Improved Methodology for Photocyclization Reactions
Liu, Longbin,Yang, Bingwei,Katz, Thomas J.,Poindexter, Michael K.
, p. 3769 - 3775 (2007/10/02)
To photocyclize stilbenes, a stoichiometric amount of iodine plus propylene oxide in the absence of air is superior to a catalytic amount of iodine in the air.The propylene oxide prevents HI from photoreducing double bonds.The absence of air prevents photooxidative side reactions, shown in one case to be caused by a photogenerated oxidant, possibly hydrogen peroxide.
Photochemistry of Electron-Rich 1,3-Distyrylbenzenes
Noller, Klaus,Kosteyn, Frank,Meier, Herbert
, p. 1609 - 1616 (2007/10/02)
The 1,3-distyrylbenzenes 3, containing up to seven alkoxy groups, are subjected to the oxidative photocyclization.Elimination of methanol (3bb -> 7bb, 3bf -> 7bf) and quinone oxidation can occur as competitive or consecutive reactions in the formation of the products 6, 7, and 8.Selfsensitized generation of singlet oxygen by 6bf can lead to endoperoxide formation (6bf -> 11).
Photochemistry of 1,3-Distyrylbenzene - A New Route to syn-(1,3)Cyclophanes
Zertani, Rudolf,Meier, Herbert
, p. 1704 - 1715 (2007/10/02)
Depending on the reaction conditions the irradiation of the title compound 1 leads to cyclodimerization 1 -> 6, dehydrogenating cyclization 1 -> 11, 12 or a combination of both processes 1 -> 13, 14, 15.The stereoisomeric (1,3)cyclophanes 6a - c as well as the access into the pyrene series 15, 16, 18 are of special synthetic interest.
trans --> cis PHOTOISOMERIZATION AND LUMINESCENCE OF THE FIVE ISOMERIC n-STYRYLPHENANTHRENES
Galiazzo, Guido,Spalletti, Anna,Bartocci, Giampiero,Aloisi, Gian Gaetano
, p. 705 - 708 (2007/10/02)
The five isomers of trans-n-styrylphenanthrene (n-StPh, with n = 1, 2, 3, 4, 9) have been prepared by standard procedures.The 4-StPh, not described in the literature, has been spectrally and photochemically characterized.The fluorescence and trans --> cis
Dibenzanthracene via Photo-cyclodehydrogenation of 9,10-Dihydro-2-styrylphenanthrene
Diederich, Francois,Schneider, Karin,Staab, Heinz A.
, p. 1255 - 1258 (2007/10/02)
Waehrend aus 2-Styrylphenanthren (1) durch Photocyclodehydrierung Benzochrysen (2) entsteht, laesst sich unter Ausnutzung der "ΣF*-Regel" aus 9,10-Dihydro-2-styrylphenanthren (4) durch Photocyclodehydrierung zu 6 und anschliessende Dehydrierung Dibenzanthracen (3) erhalten.
